Operators

Logical Operators

# Logical Operators:
==            # Test for exact equality
-lt           # Less than
-ge           # Greater than or equal to.
-ne [or] !=   # Not equal to.
-z $string    # Checks if $string is a null string.

Boolean Operators

# Boolean Operators:
||    # OR
&&    # AND

Command Operators

The || command operator in Bash is called the "logical OR" operator. It is used to execute a command only if the preceding command fails or returns a non-zero exit status.

command1 || command2    # Command error handling

From Groq:

Here, command1 is the command that is executed first. If command1 fails (i.e., returns a non-zero exit status), then command2 is executed. If command1 succeeds (i.e., returns a zero exit status), then command2 is not executed.